Activation of response codes by relevant and irrelevant stimulus information

Single-route models attribute stimulus-response compatibility effects to the difficulty of translation from stimulus to response. Dual-route models propose that compatibility effects reflect in part an additional direct, or automatic, activation route. Selected findings from three lines of research are reported that converge to provide evidence consistent with the view that the automatic activation route plays a role in compatibility effects. The data suggest that the activation produced via this route by relevant stimulus attributes influences response selection only when all mappings of stimuli to responses are known to be compatible.     

Stimulus-independent thought depends on central executive resources

Stimulus-independent thoughts (SITs) are streams of thoughts and images unrelated to immediate sensory input. Four experiments examined the contribution of aspects of working memory to production of SITs. In Experiments 1 and 2, interventions that were targeted on, respectively, phonological and visuospatial components of working memory both interfered with production of SITs, but there was evidence that these tasks also made demands on central executive resources. Experiments 3 and 4 specifically examined the hypothesis that production of SITs and control of nonproceduralized tasks both depend on central executive resources, and so should show mutual interference. In Experiment 3, prior practice on pursuit rotor and memory tasks reduced the interference with SITs from concurrent task performance. In Experiment 4, randomness within a task involving random-number generation was less when SITs were being produced concurrently than it was when they were not. The results suggest that production of SITs depends on central executive resources.     

Women preparing for traditionally male professions: Physical and psychological symptoms associated with work and home stress

Gender differences in well-being often are attributed to differential exposure of women and men to stressors, either from different distribution of the genders across roles or from different stressors within roles. An alternative hypothesis is that men and women differ in their vulnerability, although not necessarily in their exposure, to stressors. The relevant research often has confounded gender with work roles. Therefore, women and men preparing for the same traditionally male professions, as well as another group of women preparing for traditionally female professions, were included as participants in the current study (n = 397, almost all white). Even with exposure to stressors controlled statistically, nontraditional women were more susceptible than men with the same professional goals to several physical and psychological outcomes. These gender differences were not accounted for by differential vulnerability to the stressors measured in this study. However, chronic job tension and home (non-work) life events were stronger predictors of certain symptoms for these women preparing for traditionally male professions than for women preparing for traditionally female professions. Thus, both gender and career track differences were demonstrated, in susceptibility to symptoms developed and in vulnerability to stressors, respectively.     

Mental models of the earth, sun, and moon: Indian children's cosmologies

This study reports data on the acquisition of knowledge about astronomy in children from India. Based on prior research, we hypothesized that the cosmological models that children construct are influenced by both first-order and second-order constraints on knowledge acquisition. First-order constraints are the implicit assumptions that govern the construction of initial cosmological models. Examples of such constraints include the assumptions that the earth is flat and supported. Such first-order constraints are presumed to be universal. Second-order constraints arise from the specific properties ascribed to cosmological objects. For example, representations of the earth's shape and location relative to the sun and moon constrain the kinds of mechanisms that are generated to account for the day-night cycle. We hypothesized that in cultures where both folk cosmologies and the scientific cosmological model are accessible to children, aspects of folk models are likely to be incorporated in children's cosmologies if they provide a psychologically easier way of satisfying first-order constraints. This hypothesis is supported by our findings with regard to universality and culture specificity in children's cosmologies. Indian children's cosmologies honor a variety of universal first-order constraints. These include constraints on the shape of the earth (e.g., support and flatness) and on the relative locations and motions of objects in the cosmology (e.g., continuity). However, many Indian children borrow the idea that the earth is supported by an ocean or a body of water from folk cosmology. This solution to the support constraint on the shape of the earth is not found in American children's initial cosmologies.     

Recognition memory for pictures as a function of poststimulus interval: an empirical clarification of existing literature

Shaffer and Shiffrin (1972) found no effect of the duration of a blank poststimulus interval on recognition memory for visual scenes. The majority of subsequent studies, however, have found a positive relationship between interval duration and recognition accuracy. The present experiments were conducted to clarify these contradictory outcomes. Experiment 1 determined that Shaffer and Shiffrin's results are replicable with the method that they used in which stimulus durations and poststimulus-interval durations vary randomly within the study list. Experiments 2-3 showed that this random intermixing of durations is the critical factor that results in poststimulus interval having no effect. The results were interpreted in terms of a voluntary rehearsal process that is abandoned when there is uncertainty regarding the time of onset and offset of the stimuli.     

The influence of metacontrast masking on detection and spatial-choice judgments: an apparent distinction between automatic and attentive response mechanisms

Several studies of metacontrast masking in the 1960s apparently showed that the latency of simple detection responses was uninfluenced by the phenomenal dimming of the target induced by the mask. More recent studies using more suitable methodologies have clearly shown that such is not the case for situations in which the masking is a monotonically decreasing function of stimulus onset asynchrony. Experiment 1 investigated this issue for the situation in which masking is a U-shaped function of stimulus onset asynchrony. Contrary to the results obtained in monotonic masking situations, simple detection responses were not slowed by the masking. Experiment 2 demonstrated that although detection responses are not slowed in the U-shaped masking situation, spatial-choice judgments are. Experiments 3 and 4 indicated that this masking effect on spatial-choice reaction time is lost relatively rapidly with practice. However, changing the stimulus-response assignments reinstates the effect. The experiments suggest that for the situation in which U-shaped masking functions are obtained, responses that require attention (spatial-choice judgments early in practice or after stimulus-response relationships have been switched) are influenced by the metacontrast-induced phenomenal dimming, whereas responses that are automatic (i.e., detection responses; practiced spatial-choice judgments with consistent stimulus-response mappings) are not.     

Drawing inferences from semantically positive and negative implicative predicates

Subjects were timed while they drew inferences from syntactically affirmative and negative sentences containing the semantically positive and negative implicative predicates remember/forget and bother/neglect, under different linguistic contexts that met the presuppositions of the sentences at varying levels of generality. Different patterns of inference latencies were obtained for the two implicative predicates studied, suggesting that there are important differences among semantically negative implicative predicates that influence their representation and processing. Regardless of these differences, inference latencies for all sentences decreased when they were presented in contexts that met some of their presuppositions, indicating that context can facilitate inferential processing.     

Aparametric investigation of multiletter matches

Proctor (1981) presented a theoretical framework that distinguishes factors contributing to disparities in time to classify physical-same, name-same, and different letter pairs as a function of three variables: method of presentation (simultaneous vs. successive), case relationship (samecase vs. opposite-case pairs), and blocking (blocked vs. mixed presentation of same-case and opposite-case pairs). He also argued that these variables were critical in multIletter matches, and performed a between-study comparison of existing data to support his contention. Because comparison across studies is always a tenuous process and because the absence of several relevant conditions precluded a complete analysis of predictions, a within-experiment manipulation of the three relevant variables was desirable. The present study reports such an experiment. In general, the factorial manipulation of variables supported predictions of Proctor’s framework and indicated that many phenomena of multiletter matching, including the widely studied fast-“same” phenomenon, are attributable primarily to differences in the rate at which component letter pairs are matched.     

Secondary task modality, expectancy, and the measurement of attentional capacity

Previous studies have obtained conflicting evidence regarding the effect of probe modality when a secondary probe task is used to measure attentional demands of a primary letter-matching task. The present experiments found no difference in the shape of the probe reaction time functions for auditory and visual probes as long as probe modality was known. When probes "unexpectedly" occurred in the modality that was different from the majority of the probes, differences were obtained. Only the unexpected auditory function changed, shape relative to the others, with reaction time to probes that occurred early in the matching task sequence being increased. The results are interpreted as supporting a role of attentional capacity in the activation of structures that accept relevant sensory input.